In order to transmit a two dimensional array of digital data over a highly distorting channel, it is known to convert each channel to analog and then mix the channels withorthogonal carriers before adding them together. Similarily, it is known to them demodulate the ortogonal signals at theother end before converting them back to a digital form. The signal at that point is known to have two problems, that which can be thought of as "cross talk" between the two channels and the distortion caused by the channel itself. Various kinds of equalizers have been used at that point in an attempt to solve those two problems including a class of equalizers known as decision-feedback equalizers.